Air-break switch



F. BECHOFF AND M. M. SAMUELS.

AIR BREAK SWITCH. APPLICATION FILED J'AN.13,1917- Patented Mar. 2s, 1920.

INVE TOR L 152 UNITED STATES PATENT OFFICE. Z

FERDINAND BECHOFF AND MAURICE M. SAMUELS, OF NEW YORK, N. Y.

AIR-BREAK SWITCH.

Specification of Letters Patent.

Patented Ma1y23, 1920.

Application filed January 13, 1917. Serial No. 142,332.

To allcvhom it may concern Be it known that we, FERDINAND BECHOFF and MAURICE M. SAMUELs, citizens of the United States, and residents of the city of I New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Air-Break Switches, of which the following is a speclfication. 1

Our invention relates to an improvement in electric air break switches, and more particularly to air break switches used in connection with high'voltage systems.

Such air break switches are usually provided with horns for'breaking the are after the switch is opened. With increasing voltage these horns also increase in sige as well as inweight, and even with large horns it often happens that the arc fails to eX- tinguish itself.

The object of our invention is to provide a reliable and eflicient device whereby the arc will be extinguished in a reliable manner every time after the switch is opened and at the same time to make it possible to reduce the size of the horns.

In carrying out our invention the operating mechanism of the air break switch is con nected with a device wherein compressed air is produced and released, either in cooperation with the operation of the switch .or independent of the same, making the supply of compressed air available, whenever it is required. Said compressed air, directed toward the gap between the horns will materially assist to extinguish the opening arc.

Compressed air has been used before for the purpose of extinguishing an arc. Such compressed air is generally obtained from expensive and wasteful air tanks or compressors, it being necessary with such. arrangements to have a continuous supply of compressed air ready at all times. Since air break switches are only seldom opened the installation of compressors and tanks for the above mentioned purpose is neither practical nor reliable.

Our invention will be best understood in connection with the accompanying drawoperating with a device for pressed air.

Fig. 2 shows part of a projection of Fig. 1.

Fig; 3 shows a section of the air compressing device.

The form of air break switch shown in. the drawing is mounted on an iron framework 1 which supports a cylinder 2 for producing compressed air. The air break switch consists of a blade 3 which is fastened to an insulator 4. In the closed position of the switch as shown, said blade is in contact with the contact 5 on insulator 6 which has a stationary horn 7. The other horn 8 forms a part of blade 3. One end of the line (not producing comshown in drawing) is connected to contact 5 and the other end of the line in a suitable manner to a point of blade 3 where same is fastened to insulator 4. Insulator 4 holding'blade 3 is connected rigidly to shaft 9, which is supported by bearlngs 10 mounted on frame 1. Said shaft 9 is coupled to another shaft 11 by means of coupling 12 as shown in Fig. 2. To shaft 11 is fastened lever 13 which is connected on one end to the operating rod 14 of the switch and on the other end to the piston rod 15 of the air compressor. Operating rod 14 is coupled to hand lever 16 which is hinged in crank hanger 17 L As mentioned above, the air break switch is shown in Fig. 1 in its closed position. If, however, handle lever 16 is brought into its dotted position switch rod 14 will move downwarduntil coupling 18 reaches its dotted position and lever 13 its dotted position. Since lever 13 is rigidly fastened to shaft 11 and shaft 11 coupled to shaft 9, the movement of lever 13 to its dotted position will cause shaft 11 to rotate in bearings .10 in same direction as lever 13. Furthermore,

since insulator 4 is rigidly fastened to shaft 9 which is coupled to shaft 11 the rotation of said shaft 11 will cause said insulator 4 'to move to its dotted position. At the same arc. A preferred construction for securing this result is shown in the drawing in section in Fig. 3 and consists preferably of a cylinder 2 in which moves an air tight piston 20 which is pivotally connected to piston rod 15 and brought in cooperation with lever 13 by means of cross rods 21 and 22 as shown in Figs. 1 and 2. The position of the piston in Fig. 3 corresponds to the closed position of the switch shown in Fig. 1. If, however, the switch is to be opened, lever 13 will move to the dotted position thereby moving rod 21 upward. By this movement of rod 21, piston 20 will move inside cylinder 2 and thus cause the air inside cylinder 2 to become compressed. The escape of air from cylinder 2 through opening 23 during the process of compression, i. 6. during the process of opening ,the switch is prevented by valve 24 which is ressed on its seat by a suitable spring 25. Toward the end of the stroke of piston 20 the compr ssion'of the air reaches a. degree hi h en gh to overcome the pressure of spri g 25. This in turn will open valve 24 and allow the compressed air to escape through outlet 26 to a convenient point near gap 19. Thiscompressed air will materially assist in extinguishing the arc and in cooling the contacts. referably outlet 26 is made partly of insulating material and terminates at its upper end in a nozzle 27. Said nozzle serves a double purpose; firstly to properly direct the stream of compressed air, and secondly to preventv snow, ice or other substances from accumulating on top of outlet 26.

When the switch is closed again piston 20 will simultaneously come back to its original position as shown in Fig. 3. In order to allow the air to flow freely into cylinder 2 during the outward movement of piston 20 an opening 28 is provided in piston 20 which is closed by a spring operated valve 29, said valve opening when piston moves outward and closing when piston moves in-. ward.

, It is of course possible to provide two separate mechanisms one for opening and closing the switch and the other for operating the air compressing device. .When using one common mechanism as shown in the drawing means have been provided incase of emergency to disconnect the switch from the operating mechanism, which will allow the operator to continue the blowing of compressed air against the are, leaving the switch in its open position.

In order to obtain this purpose coupling 12 as shown in Fig. 2 can be shifted by means of lever 31 in such a way that shaft 9 is disconnected from shaft 11.- This makes it possible 'to rotate shaft 11 and with it lever 13 without rotating shaft 9. This in turn will leave insulator 4, blade 3, and horn 8 in their respective dotted positions, which represent the open position of the switch.

Since lever 13 can thus be moved inder. pendently of the position of the switch it becomes possible to operate the piston of the air compressor and thus produce and release compressed air repeatedly in the same manner as described above, leaving the switch in its open position. The shifting of coupling is preferably done in a well lmown manner by means of alever 31 to which is attached-a rope or chain 32 which extends within reach of the operator (Flg. 1). Means are provided to recouple shafts 9 and 11 for the purpose of closing the switch. Shaft 9 can of course be made long enough to contain any number of switch units instead of one unit, as shown in Fig. 2.

It is further possible but not practicable to arrange the mechanism in. such a way that the air would be compressed during the closing of the switch and released when the switch is'opened.

Our invention may be embodied in many other forms from that shown and described. We therefore do not wish to be restricted to the precise arrangement disclosed, since various modifications and changes may bepressor actuated by said control mechanism when opening the switches and means whereby said control mechanism can be disengaged from the switch blade, with the switch in its open position, whereby the.

operation of said air compressor can be continued until the arc is extinguished.

2. In combination, a switch blade for opening and closing an electric circuit, an air compressor for projecting an air blast across the air gap formed by moving said blade to its open position, mechanism for operating said compressor, and a-coupling for connecting said mechanism and said blade or disconnecting the same as desired,

whereby said blade and compressor may be operated simultaneously or said compressor maybe operated without operation of said blade.' a

Signed at city of New York in the county of New York and State of ew York, this twelfth day of January, A. D. 1917.

FERDINAND BECHOFIF. MAURICE M. SAMUELS. Witnesses:

CAROLYN E. JONES, LILLIAN H. PARIS. 

